QUNU (Sapa-AFP) - Nelson Mandela, South Africa's anti-apartheid hero feted worldwide after turning 90, was toasted by leaders at a lavish feast Saturday as he prepared finally to bow out of public life.

Guests stood and cheered and a choir sang "Here is our hope" as Mandela entered a festive tent set up outside his rural home for a birthday celebration.

"As you know, I am not a speaker at all, and I am not going to make any exception on this occasion, except to say thank you for all you have done for me," Mandela said in response to a champagne toast.

Former deputy Thabo Mbeki, who succeeded Mandela as head of state in 1999, and Jacob Zuma, head of the ruling ANC party and tipped to become president next year, were among the first of 500 guests to arrive for the lavish celebrations in the rural Eastern Cape.

After 27 years in prison for opposing the apartheid regime, Mandela walked free in 1990. Four years later he was elected president and led South Africa from white minority rule to democracy, setting the divided nation on the road to reconciliation.

Mandela's fellow Nobel peace prize winner Desmond Tutu also attended Saturday's feast, which included traditional food such as tripe and sheep's heads. Also present was former Zambian president Kenneth Kaunda, who sang a solo chorus of "Happy Birthday."

Heavily armed police remained on duty at his homestead in the village of Qunu, barring entrance to a number of would-be gatecrashers not on the guest list.

"Unfortunately we had to politely turn them away, irrespective of their stature," Mandela's grandson Mandla said.

Those closer to Mandela urged personalities from home and abroad to allow him to live out his remaining days in peace, surrounded by his loved ones.

"The world knew of Mandela when he was just an iconic photograph," Mary Robinson, former president of Ireland, UN Commissionner for Human Rights and a member of Mandela's Elders group which aims to tackle world problems, told the Saturday Star newspaper.

"I think we can go back to that without him being there. I wish him as happy a birthday as the world will allow him."

"His public appearances will be restricted and priority will be given to meeting with his friends, comrades and family," Achmat Dangor, chief executive of the Nelson Mandela Foundation, told the newspaper.

"In the past year, Mandela had more than 253 meetings ... For any retired person this would be gruelling, and especially for someone of 90."

Although Mandela formally retired four years ago, he has continued to raise millions of dollars for victims of the AIDS pandemic and to help underprivileged children through his charitable foundation.

Saturday's guests gathered under a large white tent decorated with the blue and orange colours of Mandela's Xhosa tribe and with his clan's crest of a bee flanked by tree branches, symbolising industry, community and strength.

Black or white, many wore traditional Xhosa attire complete with beads and animal skins.

As the party started, herd boys beat drums outside, while an orchestra played inside.

While Mandela spent his birthday -- and the 10th anniversary of his marriage to his third wife Grace Machel -- with his family on Friday, Saturday's event gave some of his admirers a chance to express their wishes in person.

"We would like to thank him (for) what he has done for us, what he has done for the people of South Africa," Mbeki said in a televised interview. He called Mandela a "great liberator."

Recorded video messages from US presidential contender Barack Obama and Tutu would also be shown at the Nelson Mandela Museum, near Qunu, a family member told AFP.

Zuma said on Saturday that Mandela's legacy reminded rulers to lead by the will of the people, defend democracy and never discriminate.

"You are the glue that holds us together as a nation. You provide eternal hope in our people and the world, that South Africa can only be a better place each day," he said.

Nelson Mandela's granddaughter Nandi Mandela called on his fans to emulate him by "making a difference in your own communities." "This is one of the gifts you can give him," she said as her grandfather nodded.